Italy, Tuscany (Livorno), Rosignano Solvay, Spiagge Bianche, 43°22'27.58"N, 10°26'21.27"E, 22.iii.2019, M. Violi leg., 1♂ and 1♀ (University of L’Aquila).

One male and one female of B. violacea were found, not far from each other, wandering on the sand among the vegetation of the shifting dunes of the Spiagge Bianche (Ligurian Sea, Tuscan coast) (Fig. 1). This site is probably the best preserved of the entire beach, away from the aphytoic belt, that is the vegetation-free zone closest to the water, disturbed in summer by bathers and periodic cleaning. The vegetation consists exclusively of herbaceous essences, mainly Ammophila arenaria arundinacea H. Lindb. (Poaceae). On the shoreline, and near the place of the finding, there were numerous trunks, branches and other plant debris carried by the storms. The area is part of the Mediterranean macrobioclimate, low meso-Mediterranean belt and low sub-humid umbrotype (Bertacchi et al. 2016). The finding of the specimens occurred around 5.00 pm on a sunny day with sparse clouds. The site was in the portion of the dunes between the mouths of the Fine and Fosso Bianco rivers. The characteristic white color of the sand is due mainly to the waste deposits derived from the production of calcium carbonate and calcium bicarbonate by the Solvay chemical industrial center (opened in 1916 and still in operation), which is located about a hundred meters behind the place where B. violacea was found. About 1.6 km north lies the village of Rosignano Solvay with the tourist port of Cala de’ Medici; about 2.4 km south is the commercial harbor of Vada, a docking point for LNG and ethylene tankers whose contents are destined for Solvay. These two sites would therefore constitute the closest sources for a possible anthropic introduction of the species to this area.

The collected specimens show shape, sculpture and color typical of the species, as described by Lucas (1847, 1849). The head, pronotum, scutellum and elytra are clearly metallic violaceous in the male (Fig. 2), while they are green-blue in the female. Both the male and the female are apterous. The apices of the elytra are regularly rounded (Fig. 2), differently from B. obliqua where the elytra are more strongly curved along the inner margin than along the outer one (Beenen 2019). The median lobe of the aedeagus (Fig. 3) has a little-sclerotized ventral surface, curved sides, and an asymmetrical apex in ventral view; the apex is regularly constricted and ends in a sharp triangle, differently from B. obliqua where it is expanded towards the apex and ends in a blunt triangle (Beenen 2019); the median lobe is straight up to the apex in lateral view; the basal part is swollen dorsally and with lateral hook-shaped extensions ventrally; the sclerite of the internal sac ends in three sharp teeth (Fig. 3). The spermatheca (Fig. 4) has hook-like, thickset cornu not inserted into the nodulus; a globose and wrinkled nodulus, as large as the cornu; and ductus with a very robust and conical proximal part.

♂: LB = 7.07 mm; LP = 1.30 mm; WP = 2.21 mm; LE = 4.13 mm; WE = 3.12 mm; LAN = 3.43 mm; LA = 55:20:34:25:25:26:26:30:31:30:41 (right antenna); LAED = 1.9 mm; LE/LP = 3.18; WE/WP = 1.41; WP/LP = 1.70; WE/LE = 0.75; LAN/LB = 0.48; LE/LAED = 2.17. ♀: LB = 6.80 mm; LP = 1.32 mm; WP = 2.24 mm; LE = 4.06 mm; WE = 3.09 mm; LAN = 3.44 mm; LA = 56:23:35:27:24:31:23:25:30:30:40 (right antenna); LSP = 0.32 mm; LE/LP = 3.08; WE/WP = 1.38; WP/LP = 1.70; WE/LE = 0.76; LAN/LB = 0.50; LE/LSP = 12.69.

Algeria: Lac Tonga, surroundings of Lacalle [= El Kala]; Djurdjura; Annaba [= Bône] (Lucas 1849; Joannis 1865; Warchalowski 2010); Morocco (Jolivet 1967, indefinite locality), and Tunisia: Aïn Draham and Téboursouk (Beenen 2019); Italy: Tuscany (Livorno), Rosignano Solvay (Fig. 1).

The only data available on the host plants of B. violacea are by Jolivet (1967, as Galeruca violacea): Pulicaria odora L. (Asteraceae), Rumex acetosella angiocarpus Murb. and Rumex scutatus induratus Boissier (Polygonaceae). However, these data require future confirmation.